Improvement in slide-valyes for steam-engiimes



` valve which is turnedto fitthe same.

` time@ IsAAc WILLIAM FORBES, OF LA PORTE, INDIANA.

1`llvlpuoingiwr-:NT` in 'SLIDE-VALVES. FOR vsfrEAlvi-E,llleini:s.

` Specifcationfoiming part ofLetters Patent No. 115,298, dated May 30', 1871.

` I, 1sAAo`FoEBEs, of La Porte, in the county of` La Porte and State of Indiana,

`have invented certain Improvements in Slide- Valves for Steaml or Air Engines, of which the followingis a speciication:

This valve receives steam in its middle through the stem, and the steam passes through it into ports corresponding. The outer ends of the valve just cover the ports when the valve is fin its center., The moment that it is moved either way from that itcommences to exhaust onthe side from which it is moved in the steam-chest, and so through the exhaust-pipe designed for the same.

Where live steam would be used with the common valve in the steam-chest, in this valve exhaust steam passes through `and out.

Description of the Accompanying Drawing.

Figure 1 is a longitudinalcentral section of my double equilibrium `female slide-valve, showing steam-chest, ports, stuffing-boxes, a double stuffing-bemand induction-pipe. Fig.

`2 is a section of the same, shown in the dotted lines a a. Fig. 3 is a longitudinal central section of avalve-stem with, one valve fitted valves divided in opposite quarters from that,

in Figs. 3 and 4., and on smaller scale from that of the former iigures. Fig. 6 is a longitudinal central Asection of a double valve, stem, and valvesiof the samesize of Fig. 5, showing another method of constructing the saine. Fig. 7 is an endview of a stem, frame, and valves `inserted therein. Fig. Sis a view of that part of the valve which plays over the seat.` Fig.

i9 is alongitudinalcentral section of Fig. 8.

Fig. 10 is a longitudinal central section'of a double or vtwofold valve,designed to be used` for a double engine when both engines are to run alike. Fig. 11 is the'valve-seat and ports. Fig. 12 shows endviews of two valves, the upper one with the packin g-band removed, the

"through the valves.

lower one with it on. Fig. 13 shows a side view of the same valve, the` upper having the packing-band removed, the lower one with it on. Fig. 14 is a top view of a valve, Valvestem, gland, and double gland. Fig. l5 is the inside view of a valve. Fig. 16 is a longitudinal central section of a double equilibrium female slide-valve, and showing another method of constructing it. Fig. 17 is a longitudinal central section of a valve, valve-stem, and steam-chest, divided in opposite quarters from that in Fig. 16. Fig. 18, the valve, valveframe, and the valve-stem as it belongs in the steam-chest. Fig. 19 is a longitudinal central section of a quadruple valve, constructed in the manner shown in Figs. 16 and 17, and on a smaller scale.

In the drawing, AAis a portion of the steamcylinder, through which the steam-passages proceed from the ports to the cylinder; A1 A1, steam-passages;l A2 A2, steam-ports in chambers in the steam-chest, which convey the steam round the sides of the same into the cylinder; A3 A3, steam-passages through the sides of the steam-chest into the ports in the cylinders from the ports in the steam-chest cover. B Bare valves. These valves have Shanks or pistons upon that portion which fits in their frame. B1 B1 are steam-passages B2 B2 are steam-packing rings similar to those used in pistons for the purpose of preventing the passage of steam between the valve and its frame. C C are bosses on valve-stern, bored out to receive the Vvalve which forms the frame; G1, steam-passage through valve-stem kC2, valve-stem 5 C3 C?, the valve-stein, Wh'ich has a square mortise through the saine. E E'are glands. F is an induction-steam pipe. F1 is gland and stuffing-box. G G steam-chest through which eX- haust steam passes into exhaust-pipe. h hare glands usedin place ofthe steam-packing ring. H H are the two sides ofthe valve-frame, with stuiing-boxes dressed out for the purpose of receiving stuffing and glands to form a steamtight joint between the valves and frame. the place of bands H H two sides, H H, may have a iiange upon each half of the tight joint,

and bolted together, which will have the same eiect as bands H H', andreceive the valvestem in the same way.

FFIOE.

Ola/5ms.

1. The valve or valves B B, valve-frame C C, and steam-passages B1 B1 C1,substantia1iy as and for the purpose described.

2. The valves B B, in combination with H H and H H', substantially as and for the purpose described.

3. The valves B B, in combination with Valve-stems C2 and bosses, substantially as described.

I. W. FORBES. Witnesses:

W. E. FINCKEL, W. J. PEYTON. 

